JP5723187B2 - Multi-chip substrate - Google Patents

Description

  The present invention relates to a multi-chip substrate used when manufacturing a wiring substrate used for, for example, a SAW filter package or a duplexer package.

  In general, when a wiring board is manufactured, a so-called multi-piece substrate in which a plurality of wiring boards are formed on one large-sized board is used. This type of multi-piece substrate is composed of a central wiring board region in which a plurality of wiring boards having via conductors and wiring layers are arranged vertically and horizontally, and a ceramic layer formed so as to surround the periphery of the wiring board region. And a frame portion.

  Further, in recent years, a reduction in the thickness of a multi-piece substrate has been remarkable in order to reduce the size of the entire component, and thus a problem has arisen that the multi-piece substrate is warped. As a countermeasure, a technique has been proposed in which a plurality of line-shaped metallization layers are formed so as to surround the entire periphery of the wiring board region along the outer periphery of the frame portion (see Patent Document 1).

  When manufacturing a multi-chip substrate by this conventional technique, an area corresponding to a plurality of multi-chip substrates (a multi-chip substrate area) is formed on a large green sheet, and then each multi-chip substrate is formed. A metallized layer is formed along the outer peripheral edge of the substrate substrate area, and then each multi-chip substrate region is cut along the metallized layer to separate each multi-substrate substrate green sheet. Thereafter, the multi-chip substrate was manufactured by firing the green sheet for each multi-chip substrate region.

JP 2006-278808 A

  However, in the above-described prior art, the warping of the multi-cavity substrate is solved, but when the multi-cavity substrate is transported, the corner portion of the multi-cavity substrate is reduced. No consideration has been given to the problem of chipping or cracking.

  Further, in the above-described prior art, each multi-piece substrate region is cut at the location where the metallized layer is formed. Therefore, when the cutting is performed, cutting pieces of the metallized layer may adhere to the multi-piece substrate region. Therefore, after firing the green sheet of the multi-chip substrate area, if the metallized layer cutting waste remains on the multi-chip substrate, problems such as short circuit may occur on the multi-chip substrate and each wiring board. there were.

  The present invention has been made to solve the above-described problems, and its purpose is to suppress the occurrence of chips and cracks, and to attach a substance that causes a short circuit to a multi-chip substrate or a wiring board. It is to provide a multi-piece substrate that can suppress the above.

(1) The present invention, as a first aspect, is a multi-piece substrate mainly composed of ceramic and having a rectangular shape in plan view, wherein a plurality of wiring substrates are arranged vertically and horizontally in a planar direction; A frame portion disposed so as to surround the entire circumference in the planar direction of the wiring board region, and a metallized layer formed along an outer periphery in the planar direction of the frame portion, the metallized layer comprising: It is formed so as to cover all the corners of the outer periphery, and is provided with a non-formation region where the metallized layer is not formed between the corners and the corners, and a recess on a predetermined side of the multi-cavity substrate. Is provided, the width of the metallized layer on the side provided with the concave portion is larger than the width of the metallized layer on the side not provided with the concave portion .

In the present invention, the metallized layer formed along the outer periphery of the frame part is formed so as to cover all corners of the outer periphery of the frame part, and the metallized layer is provided between the corner parts. The non-formation area | region which is not formed is provided.

  Therefore, even when the multi-piece substrate is thinned, for example, 0.15 to 0.3 mm, the corners are covered with the metallized layer. There is an effect that chips and cracks are hardly generated.

Furthermore, in the present invention, since the formation range of the metallized layer is small, when cutting the multi-piece substrate region from the green sheet, it is difficult for the metallized layer cutting scraps to adhere to the multi-piece substrate region. When the green sheet in the substrate region is fired, there is an effect that a short circuit hardly occurs in the multi-piece substrate and the wiring substrate.
The side where the concave portion is formed is liable to be chipped or cracked due to a racking at the time of plating and a handling mistake at the time of removal work. In the first aspect, the width of the metallized layer on the side where the concave portion is formed ( Since it is set wider (compared to the side that is not so), it is possible to suitably prevent the occurrence of chipping and cracks on the side where the recess is formed.
In the above-described invention, the length of the metallized layer formed on each side of the multi-cavity substrate is preferably in the range of 40 to 80% of each side. If it is this range, the prevention of the chip | tip and crack in a corner | angular part and the prevention of the adhesion of the cutting waste of a metallized layer in a manufacture stage can be made compatible suitably.

(2) As a second aspect of the present invention, the corners are four corners of a rectangular multi-chip substrate.
Here, corner portions are illustrated. Although the corners at the four corners of the rectangular substrate are easily damaged, the formation of metallization layers at the corners can prevent the corners from being chipped or cracked.

(3) The present invention is characterized in that, as a third aspect, when a predetermined side of the multi-cavity substrate is provided with a concave portion, the corner portion is an open end of the concave portion.
Here, corner portions are illustrated. If there is a recess on the side of the rectangular substrate, the opening end (which becomes a corner) of the recess is easily damaged, but by forming a metallized layer on this opening end, the occurrence of chipping or cracking at the opening end is prevented. it can. This recess can serve as a contact terminal for plating, but also has an effect of preventing breakage of the recess that occurs when the contact terminal is attached.

( 4 ) The present invention, as a fourth aspect, is a multi-piece substrate mainly composed of ceramic and having a rectangular shape in plan view, wherein a plurality of wiring substrates are arranged vertically and horizontally in a planar direction; A frame portion disposed so as to surround the entire circumference in the planar direction of the wiring board region, and a metallized layer formed along an outer periphery in the planar direction of the frame portion, the metallized layer comprising: It is formed so as to cover a plurality of corners on the outer periphery, and is provided with a non-formation region where the metallized layer is not formed between the corners, and further, a predetermined side of the multi-cavity substrate The width of the metallized layer on the side provided with the concave part is larger than the width of the metallized layer on the side not provided with the concave part.
In the present invention, the metallized layer formed along the outer periphery of the frame is formed so as to cover a plurality of corners on the outer periphery of the frame, and the metallized layer is provided between the corners. The non-formation area | region which is not formed is provided.
Therefore, even when the multi-piece substrate is thinned, for example, 0.15 to 0.3 mm, the corners are covered with the metallized layer. There is an effect that chips and cracks are hardly generated.
Furthermore, in the present invention, since the formation range of the metallized layer is small, when cutting the multi-piece substrate region from the green sheet, it is difficult for the metallized layer cutting scraps to adhere to the multi-piece substrate region. When the green sheet in the substrate region is fired, there is an effect that a short circuit hardly occurs in the multi-piece substrate and the wiring substrate.
In addition, the side where the concave portion is formed is liable to be chipped or cracked due to mishandling during racking and removal work during plating, but in this fourth aspect, the metallized layer on the side where the concave portion is formed Since the width is set wider (compared to the side that is not so), it is possible to suitably prevent the occurrence of chipping and cracks on the side where the recess is formed.
In the above-described invention, the length of the metallized layer formed on each side of the multi-cavity substrate is preferably in the range of 40 to 80% of each side. If it is this range, the prevention of the chip | tip and crack in a corner | angular part and the prevention of the adhesion of the cutting waste of a metallized layer in a manufacture stage can be made compatible suitably.

It is a top view of the multi-cavity substrate of the reference form which is a premise of the present invention . (A) is AA sectional drawing in FIG. 1, (b) is a side view of a multi-piece substrate. (A) is explanatory drawing which expands and shows a part of corner part of the four corners of a multi-cavity board | substrate, (b) is explanatory drawing which expands and shows the recessed part of a multi-cavity board | substrate. It is explanatory drawing which shows the manufacturing method of a multi-piece substrate. It is a top view of the multi-cavity substrate of the reference form which is a premise of the present invention . It is a top view of the multi-cavity substrate of the first embodiment.

Hereinafter, embodiments of the present invention will be described.
[First Reference Form]
a) First, the configuration of the multi-cavity substrate of the first reference embodiment, which is a premise of the present embodiment , will be described.

As shown in FIG. 1, the multi-cavity substrate 1 of the present embodiment has a rectangular (rectangular) plan view, and is a thin film in which two upper and lower ceramic layers 3 and 5 (see FIG. 2) made of alumina, for example, are laminated. It is a multilayer substrate (for example, thickness 0.15-0.3 mm). In addition, as a dimension of this multi-piece substrate 1, for example, 80 mm in length x 60 mm in width x 1 mm in thickness can be adopted.

  The multi-chip substrate 1 is formed so as to surround a wiring board region (gray portion at the center in FIG. 1) 9 in which a plurality of wiring boards 7 are arranged in a grid pattern in the plane direction and the entire circumference of the wiring board region 9. The rectangular frame portion 11 is formed.

Among these, in the wiring board region 9, for example, a predetermined number of wiring boards 13 having a length of 2.5 mm, a width of 2.0 mm, and a thickness of 1 mm are arranged in the vertical and horizontal directions.
As shown in FIG. 2, in the wiring board 13, a total of 12 via conductors 15 are formed penetrating in a lattice shape in the upper ceramic layer 3 constituting the wiring board 13. A surface side pad 17 is formed on the upper end surface. On the other hand, in the ceramic layer 5 on the lower layer side of the wiring substrate 13, a total of four via conductors 19 are formed penetrating in the vertical and horizontal directions, and back side pads 21 are formed on the lower end surfaces thereof. An internal wiring layer 23 that electrically connects the via conductors 15 and the upper and lower via conductors 15 and 19 is formed between the ceramic layers 3 and 5.

  The via conductors 15 and 19, the internal wiring layer 23, the front surface side pad 17, and the back surface side pad 21 are made of, for example, W or Mo, and the outer surface (on the exposed side) of the front surface side pad 17 and the back surface side pad 21. Is coated with a Ni plating film and an Au plating film (both not shown).

On the other hand, as shown in FIG. 1, the frame portion 11 includes short side frame portions 25 and 27 on the short side in the vertical direction in FIG. 1 and long side frame portion on the long side in the horizontal direction in FIG. 29 and 31.
Among these, the long side frame portions 29 and 31 are provided with a recess 41 on the outer side (left and right direction in the figure) having a semicircular planar shape (for example, a radius of 1 mm) used as an electrode for plating. Two places are provided for each.

In particular, in the present embodiment , the outer peripheral metallized layer 43 made of, for example, W or Mo is intermittently provided with a gap between the upper and lower surfaces (vertical direction in FIG. 2) of the frame portion 11 along the outer periphery of the frame portion 11. Is formed.

  The outer peripheral metallized layer 43 is a belt-like layer (for example, 10 to 20 μm thick × 1 mm wide), and has four corners (corner corners) 45 of the multi-chip substrate 1 and four concave portions on the long side. It is formed so as to cover the vicinity of 41 (particularly, the inwardly curved portion and the curved end portion (end corner portion 42)).

  Specifically, the outer peripheral metallization layer 43 is formed so as to cover 30% of the length of the short side on the short side, and is formed so as to cover 10% of the length of the long side on the long side. ing. Note that the length of the long side is assumed to be the length where the recess 41 is not recessed.

  That is, as shown in an enlarged view in FIG. 3A, the outer peripheral metallized layer 43 is formed at the corner 45 of the corner of the multi-piece substrate 1 at an end (bending point X) that bends 90 ° of the corner 45. ) From the bending point X along the long side and about 8 mm along the long side.

  Similarly, as shown in an enlarged view in FIG. 3 (b), the outer peripheral metallized layer 43, in the concave portion 41 of the multi-piece substrate 1, has a bending start point (bending point Y) at the corner 42 at the end of the concave portion 41. ) Extends about 8 mm toward the corners 45 at both corners along the long side. In addition, on the upper and lower surfaces inside the recess 41 (on the side of the wiring board region 9), the outer peripheral metallized layer 43 is formed in a semicircular shape with the same width as other portions along the curve.

In each side of the multi-chip substrate 1, a portion where the outer metallized layer 43 is not formed is a non-formed region 46 (of the outer metallized layer 43).
b) Next, a method for manufacturing the multi-cavity substrate 1 of this embodiment will be described.

A raw material composed of alumina powder particles, a resin binder, a plasticizer, a solvent, and the like was mixed in advance to produce a ceramic slurry.
Using this ceramic slurry, a two-layer green sheet having a rectangular shape (rectangular view) was formed by a doctor blade method. This two-layer green sheet is a large plate type for taking a plurality of (for example, three) multi-chip substrates 1, and a region for each multi-chip substrate 1 and a region for each wiring board 13 are set in advance. Has been.

Next, a required number of via holes were formed by punching through the formation positions of the plurality of wiring boards 13 in the green sheets for the upper layer and the lower layer.
Next, each via hole was filled with a conductive paste containing W or Mo powder pressed by a squeegee using negative pressure by suction on the opposite side to form unfired via conductors individually.

Next, the same conductive paste as described above was screen-printed on the surface of the lower layer green sheet to form an unfired internal wiring layer.
Next, the upper layer green sheet on which the unfired via conductor is formed and the green sheet for the lower layer on which the unfired via conductor and the unfired internal wiring layer are formed are laminated and pressure-bonded, and FIG. A large green sheet laminate 47 as shown in FIG.

  Next, an unfired front side pad and an unfired back side pad are formed on the upper and lower surfaces of the green sheet laminate 47 by screen printing using the same conductive paste as described above, and along the cutting line S. An unfired outer peripheral metallized layer 51 was partially formed.

  That is, when the unfired outer metallized layer 51 is formed, each unfired multi-chip substrate 49 (corresponding to each multi-chip substrate 1) is cut out from the green sheet laminate 47 as shown in FIG. An unfired outer peripheral metallized layer 51 is formed with a predetermined width (for example, twice the width of the outer peripheral metallized layer 43) so as to straddle the cut line S along the cutting line S. For example, the non-fired outer peripheral metallized layer 51 is formed outside the cutting line S with the same width as the outer peripheral metallized layer 43. The concave portion 41 forms an unfired outer peripheral metallized layer 51 along the curvature of the concave portion 41.

  Next, each unfired multi-chip substrate 49 is cut from the green sheet laminate 47 along the cutting line S using a cutter. At that time, the unfired outer peripheral metallized layer 51 is also cut simultaneously.

  The recess 41 may have a semi-circular (or circular) cutting line by punching or the like before cutting each unfired multi-piece substrate 49. After the substrate is cut, it may be cut by punching or the like.

In this reference embodiment , it is not necessary to apply metallization to the side surface of the recess 41, but it may be applied separately. When applying, you may form in the same process as the process of forming the non-baking outer metallization layer 51.

  Next, an unfired multi-chip substrate 49 on which an unfired via conductor, an unfired front side pad, an unfired back side pad, an unfired internal wiring layer, and an unfired outer peripheral metallized layer 51 are formed is formed in a predetermined temperature range. And baked to prepare a baked substrate.

  Thereafter, the electrode bar (plating rack) is brought into contact with the recessed portion 41 of the baked substrate (that is, the portion serving as the electrode for plating) to perform Ni electrolytic plating and Au electrolytic plating, and the surface side pads 17 and The surface of the back side pad 21 was coated with a Ni plating film and an Au plating film.

Thereby, the multi-piece substrate 1 was completed.
After that, each wiring board 13 was produced by cutting the multi-piece substrate 1 along the outer periphery of the wiring board 13 with a cutter. In addition, when the cutting line is previously formed before baking, you may divide each wiring board 13 into pieces by a division | segmentation.

c) it will now be described experimental example conducted for confirming the effect of this preferred embodiment.
By the manufacturing method described above, a sample in which the ratio (%) of the length along each side of the outer peripheral metallized layer was changed in each multi-cavity substrate was produced.

Specifically, in each side, the sample A in which the ratio of the length of the outer peripheral metallized layer (length along the side) is 0% (no metallization) and the sample B in which the ratio is 100% (full metallization) 10 samples C each having a metallized layer (30% on the short side and 10% on the long side) were prepared (other dimensions are the same as in the first embodiment).

  Then, using these samples, each unfired multi-chip substrate was cut from the green sheet laminate along the cutting line S using the cutter as in the manufacturing method described above (the metallized layer was also cut at the same time). However, as shown in Table 1 below, in the case of the sample C in which the outer peripheral metallization layer is partially formed, the metallized cutting waste adheres to the multi-piece substrate as compared with the sample B of the entire peripheral metallization. The ratio to do was small.

Moreover, about each similar sample, after performing Ni / Au plating after baking, the presence or absence of a crack or a chip | tip was confirmed visually.

  The results are shown in Table 2 below. In the case of the sample C in which the outer peripheral metallized layer is partially formed, compared with the sample A without the metallized layer, the corners at the corners and the corners at the ends of the recesses are shown. There were few occurrences of chips and cracks.

According to these experiments, those with an outer peripheral metallization layer formed on each side of the multi-cavity substrate can suitably suppress the occurrence of chips and cracks, and the occurrence of shorts due to the generation of cutting waste. It turns out that it can suppress.

d) As described above, in the multi-cavity substrate 1 of the present embodiment, the outer peripheral metallized layer 43 formed along the outer periphery of the frame portion 11 has four corners (corner corners) on the outer periphery of the frame portion 11. 45 and the corner of the open end of the recess 41 (the corner 42 of the end) are formed, and a non-formation region 46 in which the outer metallized layer 43 is not formed is provided between the corners 45 and 42. It has been.

  Therefore, even when the multi-piece substrate 1 is thinned, for example, 0.15 to 0.3 mm, the corners 45 and 42 are covered with the outer peripheral metallized layer 43, so the multi-piece substrate 1 is conveyed. For example, the corners 45 and 42 are less likely to be chipped or cracked. In particular, the corners 5 of the corners of the rectangular multi-cavity substrate 1 and the corners 42 of the ends of the recesses 41 are easily damaged. Can be prevented.

In addition, in this reference embodiment, since the formation range of the outer peripheral metallized layer 43 is small, when cutting the unfired multi-cavity substrate 49 from the green sheet laminate 47, a large number of uncut fired outer metallized layer 51 cuttings are unfired. Therefore, when the unfired multi-piece substrate 49 is fired, the multi-piece board 1 and the wiring board 13 are less likely to be short-circuited.

That is, in this reference embodiment, since the outer peripheral metallized layer 43 is partially formed on each side of the multi-cavity substrate 1, as is clear from the experimental example described above, It is possible to suitably achieve both prevention of cracks and prevention of adhesion of cutting waste of the unfired outer peripheral metallized layer 51 in the manufacturing stage.
[Second Reference Form]
Next, the second reference embodiment as a premise of the present invention will be described, but the description of the same contents as the first reference embodiment will be omitted.

As shown in FIG. 5, the multi-cavity substrate 51 of the second reference embodiment, which is the premise of the present invention, is a substantially rectangular ceramic substrate, similar to the first reference embodiment, and has a large number of wiring substrates at the center thereof. In addition to a rectangular wiring board region 55 in which 53 is disposed, a rectangular frame portion 57 is provided so as to surround the entire outer periphery of the wiring board region 55.

Further, on the front surface and the back surface of the frame portion 57, the outer peripheral metallized layer 63 similar to the first reference embodiment is formed along the outer periphery of the frame portion 57 in the corners 59 and the concave portions 61 of the outer periphery of the frame portion 57. I have. In addition, the formation range of the outer periphery metallization layer 63 is a range of 20 to 80% of the length of each side.

In particular, in this reference embodiment, one corner 59 of the four corners of the outer periphery of the frame 57 (and hence the multi-chip substrate 51) is cut obliquely, and the same applies to the edge of the notch 65. An outer peripheral metallized layer 63 is formed.

  In calculating the% (ratio) of the formation range of the outer peripheral metallized layer 63, it was calculated that the outer metallized layer 63 was not cut obliquely (that is, the intersection of extending the vertical and horizontal sides was regarded as a corner, and the distance from this corner was calculated. (Calculated using the distance to the end of the outer metallized layer 63).

Also in this reference embodiment, the same effects as those of the first reference embodiment can be obtained, and the notch 65 is formed at one corner 59 of the multi-cavity substrate 51. Has the advantage of being easily understood.
First Embodiment
Next, the first embodiment will be described, but the description of the same contents as the second reference embodiment will be omitted.

As shown in FIG. 6, the multi-piece substrate 71 of the present embodiment is a substantially rectangular ceramic substrate as in the first reference embodiment, and is a rectangular shape in which a large number of wiring boards 73 are arranged at the center. A wiring board region 75 is provided, and a rectangular frame portion 77 is provided so as to surround the entire outer periphery of the wiring board region 75.

  Further, on the front surface and the back surface of the frame portion 77, the outer peripheral metallization layer 83 similar to that of the second embodiment is formed along the outer periphery of the frame portion 77 in the corners 79 and the concave portions 81 of the outer periphery of the frame portion 77. I have. In addition, the formation range of the outer periphery metallization layer 83 is a range of 20 to 80% of the length of each side.

  Furthermore, also in this embodiment, one corner 79 on the outer periphery of the frame 77 (and hence the multi-chip substrate 71) is cut obliquely, and the outer edge of the notch 85 is similarly outer. A metallized layer 83 is formed.

  In particular, in the present embodiment, the width of the outer metallization layer 83 on the long side (left-right direction in the figure) is larger than the width of the outer metallization layer 83 on the short side (vertical direction in the figure) (for example, twice as large). Width) is set.

  In the present embodiment, the same effect as in the second embodiment is obtained, and the width of the outer metallization layer 83 on the long side (that is, the side having the recess 81) is set larger than that on the short side. Even when a plating member (plating rack) hits the recess 81 during plating, there is an advantage that the long side is not easily damaged.

In addition, this invention is not limited to the said embodiment at all, and it cannot be overemphasized that it can implement with a various aspect in the range which does not deviate from this invention.
(1) For example, the ceramic forming the multi-chip substrate is not limited to alumina, but may be aluminum nitride, mullite, or a glass-ceramic that is a kind of low-temperature fired ceramic.

(2) Further, the multi-piece substrate may be formed of a single ceramic layer or a multilayer ceramic substrate in which three or more ceramic layers are laminated.
(3) The end surface of the via conductor may be plated without forming the front surface side pad or the back surface side pad on the exposed end surface of the via conductor of the wiring board.

DESCRIPTION OF SYMBOLS 1, 51, 71 ... Multi-piece substrate 3, 5 ... Ceramic layer 9, 55, 75 ... Wiring board area | region 11, 57, 77 ... Frame part 13, 53, 73 ... Wiring board 15, 19 ... Via conductor 17 ... Surface Side pad 21 ... Back side pad 23 ... Internal wiring layer 41, 61, 81 ... Recess 42 ... Corner corners 43, 63, 83 ... Peripheral metallized layers 45, 59, 79 ... Corner corners 46 ... Non-forming region

Claims (4)

A multi-piece substrate mainly composed of ceramic and having a rectangular shape in plan view,
A wiring board region in which a plurality of wiring boards are arranged vertically and horizontally in a plane direction;
A frame portion arranged so as to surround the entire circumference in the planar direction of the wiring board region;
A metallized layer formed along the outer periphery in the planar direction of the frame part;
With
The metallized layer is formed so as to cover all corners on the outer periphery of the frame part, and includes a non-forming region where the metallized layer is not formed between the corners and the corners,
In the case where a recess is provided on a predetermined side of the multi-cavity substrate, the width of the metallization layer on the side having the recess is larger than the width of the metallization layer on the side not having the recess. Single substrate.   The multi-cavity substrate according to claim 1, wherein the corners are four corners of a rectangular multi-cavity substrate.   3. The multi-piece substrate according to claim 1, wherein the corner portion is an open end of the concave portion when a concave portion is provided on a predetermined side of the multi-piece substrate. A multi-piece substrate mainly composed of ceramic and having a rectangular shape in plan view,
A wiring board region in which a plurality of wiring boards are arranged vertically and horizontally in a plane direction;
A frame portion arranged so as to surround the entire circumference in the planar direction of the wiring board region;
A metallized layer formed along the outer periphery in the planar direction of the frame part;
With
The metallized layer is formed so as to cover a plurality of corners on the outer periphery of the frame part, and includes a non-forming region where the metallized layer is not formed between the corners and the corners. The multi-cavity substrate is provided with a recess on a predetermined side of the multi-cavity substrate, and the width of the metallization layer on the side having the recess is larger than the width of the metallization layer on the side without the recess. substrate.